Method and apparatus for executing repeatable golf swings

ABSTRACT

The present invention is a method and apparatus that helps golfers consistently execute the ideal golf swing. To consistently execute the ideal swing, golfers must be able to consistently align the shafts of their clubs at the ideal angle with respect to the ground during setup, prior to executing the swing. The present invention helps golfers achieve such consistency by mating the golf club with a level-indicating device that shows when the golf club angle matches the ideal angle. The level-indicating device is a small, lightweight bubble tube, of the type commonly found in carpenter level tools, that quickly clips onto an off of the golf club shaft. The level-indicating device is sufficiently small and lightweight that it can be used during both practice and actual play. The same device may be used on different golf clubs to show the ideal angle for the club in use.

This invention relates to a way of helping golfers develop reliable golf swing that consistently strike golf balls to produce the desired results. More particularly, this invention relates to equipping golf clubs with a device, referred to as a shaft alignment indicator, that indicates the club's actual shaft angle relative to the ideal shaft angle, thereby allowing golfers to adjust the actual shaft angel until it coincides with the ideal shaft angle. The small, lightweight, shaft alignment indicator quickly clips onto and off of the golf club shaft, allowing the device to be used in both practice and competition. The device consists of a bubble tube, of the type commonly employed in carpenter levels, affixed to a clip that snaps onto the golf shaft, at an angle equal to the ideal shaft angle.

BACKGROUND OF THE INVENTION

Numerous training aids and golf club designs have been developed to help golfers develop and consistently replicate the ideal swing. Such training aids have generally been of three types; those that attempt to control the motion of the golfer's body; those that attempt to control the motion of the golf club; those that help golfers direct the club along an ideal path. The present invention fits into the later category. The first two categories will be reviewed first.

Meeker and Crouch, U.S. Pat. No. 4,815,743 disclose a large circular plate, termed a member, mounted on a support structure at an angle corresponding to the ideal swing plane. The golfer sticks his head through an opening in one edge of the plate and practices executing his golf swing without contacting the plate. Besides the size, expense and unwieldiness of this structure, it does little to control the actual movement of the golf club and does not specify how to determine the ideal swing plane.

Romano, U.S. Pat. No. 5,474,299 discloses a system of linkages and a rotor that connects to the golfer's hand and rotates as the golfer executes his or her swing. This large mechanism is complex and does not control the important link between the club handle and club head. Further, the disclosure does not specify how to align the rotor to the ideal swing plane. Numerous other inventions that attempt to control body motion fail to address the last, critical linkage in the complex system that starts at a golfer's feet and ends at the point where the club contacts the ball, the golf club itself. This is why so much attention has been devoted to the second category of training aids, those that attempt to control the golf club.

Harper, U.S. Pat. No. 5,538,251 discloses a rotation training structure that interconnects between a vertical support structure and the golf club that purports to guide the club through a perfect swing plane. However, the inherent flexibility in the large system of mechanical linkages prevents precise control of the swing plane, whether or not it is ideal.

Dayton, U.S. Pat. No. 6,645,084 B1 discloses a swing training device consisting of a large free-spinning wheel that attaches near the head of the golf club and makes contact with the ground at the moment of contact with the ball. This system purports to help users improve timing and release of hands, but actually inhibits the type of ball striking that compresses the ball between the turf and club face that is universally recommended for irons. Further, the added weight of the system disrupts normal feel of the golf club. No training system that attempts to control the motion of the golf club works for all users. They all suffer from the disadvantages that the mechanisms, rather than the golfer, control the motion of the club and the golfer's experience with the system is different than the real-world without it. Shortcomings of these systems have led to the proliferation of training aids that attempt to influence the club to follow the ideal swing plane, rather than directly control the club's motion.

Novosel, U.S. Pat. No. 6558,267 B2 discloses a hinged training club claimed to act substantially like a conventional golf club in every way, and whose hinge breaks when the user executes a flawed swing. An advantage of this club is that it can be used both on the practice range and on a real golf course, but no real golfer wants to run the risk of the hinge breaking during a real golf swing, turning a bad swing into a catastrophic swing. Further, this system does not allow the golfer to practice with his or her own clubs.

Gauer, U.S. Pat. No. 6,945,875 B2 discloses a golf training device that includes a ball alignment marker and a template that identifies a preferred path of movement of the hand through a golf swing. The template also includes lines that identify the preferred orientations of the club face during the swing. The major shortcoming of this system and numerous similar systems is that they do not address the mechanics of actually making the club face follow the desired path and they do not account for the vertical motion of the club head through the ball and into the turf.

Numerous training aids have been invented that employ lasers that provide feedback on the orientation of the club shaft during the swing. For example, Freer, U.S. Pat. No. 4,913,441 discloses a laser swing training device that attaches to the butt of the golf club handle. The laser is intended to follow a path traced on a training mat on the ground, and in so doing help the golfer keep the club on an ideal swing The disadvantages of this and similar systems are that they can interfere with the golfer's hands and it is difficult to precisely align the laser with the golf shaft. Further, such systems direct the eyes of the golfer away from the ball during the golf swing. Variations on this system, including those disclosed by White and Burrus, U.S. Pat. No. 5,467,991, Pellegrini, U.S. Pat. No. 5,665,006, Lauffer and Parkinson, U.S. Pat. No. 5,954,592, and Marley, U.S. Pat. No. 6,059,668 all use similar approaches that suffer similar disadvantages.

Systems that influence the proper alignment of the golf club and its subsequent motion, while minimizing interference with the golfer, provide the greatest benefit to golfers. Lambert, U.S. Pat. No. 5,632,484 discloses a liquid-filled, transparent domed vial that attaches to the free-end of a golf club, and includes a bubble that indicates the angular alignment of the shaft. The problems with this system are that it is difficult to precise align the dome with the shaft to obtain accurate, consistent readings, and there is no unique position of the bubble in the dome that corresponds to the preferred shaft alignment to follow an ideal swing plane.

Spitzer, U.S. Pat. Nos. 6,468,166 B1 and No. 6,814,672 discloses systems that attach directly to the golf shaft, thereby eliminating the misalignment problem, that measure the lateral misalignment of the club face. The systems consist of alternate embodiments of curved bubble tubes, similar to the bubble tubes commonly found in carpenter level tools, but curved downward to keep the bubble at the top of the arc when the toe of the club is vertical. The major shortcoming of this system is that it does not provide the golfer with any new useful information and it ignores the more critical angle that the shaft makes with the ground. Golfers can readily perceive when the club face does not point toward the target. Further, Spitzer's inventions do not assure that the club face is square with the ball and pointing toward the target, but only that the toe of the club is vertical. Finally, the most critical shaft angle for starting and maintaining the club on the ideal swing plane is the angle that the shaft makes with the ground, which is not addressed by Spitzer's inventions

Larson, U.S. Pat. No. 6,346,050 discloses a simple system for properly aligning the club shaft with the ground. The system includes a block bored with a plurality of holes that make different angles with the ground and a stake that the golfer can insert in the various holes. To use the system the golfer aligns the club shaft parallel to the shaft stuck in the block. The major problems with this system are that it relies on the user correctly judging when the two shafts are parallel, and it is not practical to use the system during actual play.

The unmet challenge is to devise a system that helps golfers properly align the golf shaft with the ground to start the club on the ideal swing plane, yet not disrupt normal use of the golf club.

Studies have shown that the best professional golf drivers create a 45-degree angle between the club shaft and the ground at ball impact. Ben Hogan, John Daly, and Tiger Woods all create a perfect 45-degree angle. Further, most professional golfers have a shaft angle of 45 to 47 degrees at impact while most amateurs have impact angles above 50 degrees. Such high shaft angles increase both ball spin and launch angle, leading to shorter drives and flight trajectories more susceptible to hooks and slices. Deviations from the 45 degree angle on the low side also have negative consequences. For example, professional golfers Fred Funk and Cory Pavin both have shaft angles close to 40 degrees at impact. Their drives tend to go straight, but short compared to other professional golfers. A device that helps golfers start their driver shafts on the ideal 45-degree swing angle, and helps maintain that plane angle throughout the swing would help both amateur and professional golfers. Such a device is the objective of the present invention.

The present invention is distinguished from prior art in that it directly measures the angle between the club shaft and ground, contains a built-in reference to the ideal club angle, and is small enough and sufficiently light weight to not affect the golf swing. Further, the device quickly snaps onto and off of the golf club shaft, making it convenient to use during actual play.

BRIEF SUMMARY OF THE INVENTION

This invention is a method and apparatus for executing accurate, repeatable golf swings. The two components of the system are a clip that snaps onto and off of the golf club shaft, and a bubble tube, attached to the clip, that indicates the angle between the club shaft and the ground. The longitudinal axis of the clip aligns precisely with the longitudinal axis of the shaft. The bubble tube is attached to the clip at an angle such that the longitudinal axis of the shaft matches the ideal shaft angle when the bubble tube is parallel to the ground.

The clip is made of a spring material that allows it to be snapped on and off of the club shaft without damaging or scratching the shaft and without permanently deforming the clip. Further, at the user's option, the clip may be installed or removed from the club shaft by sliding the clip down the shaft axis toward the club head where the diameter of the shaft tapers down sufficiently to allow clip installation and removal without springing open the clip's retaining arms. By affixing the device directly to the club shaft, with no play in the connection, the sensing device provides consistent, accurate readings of the shaft alignment angle.

The preferred embodiment of this invention uses a downwardly curved bubble tube that has a plurality of marks that show the ideal swing angles for various clubs. Golfers use the device by aligning the bubble in the bubble tube with the marking appropriate for the club in use, and keeping the club on this swing plane throughout their swings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of the complete system, showing an exemplary embodiment of the shaft alignment device, 2, mounted to a golf club, 1.

FIG. 2 shows the preferred embodiment of the shaft alignment device, 5, equipped with a curved level-indicating device, 8.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a schematic of the entire system. The golf club, 1, is shown in the normal position as it addresses the ball, 2, lying on the ground, 3, prior to starting the swing. The club shaft, 4, makes an angle, 5, with the ground, 3. The shaft alignment device, 6, clips onto the club shaft, 4, and is pushed upward along the shaft, 4, until it rests snugly against the bottom of the club handle, 7.

The ability to quickly install and remove the shaft alignment device, 6, is important during actual play because the golfer may not want the shaft alignment device, 6, to remain on the club shaft, 4, when he places the club, 1, back into his bag. At the user's option, the shaft alignment device, 6, may be installed on the club shaft, 4, by either inserting the small end of the club shaft, 4, into the opening of the shaft alignment device, 6, then sliding the shaft alignment device, 6, up the club shaft, or simply snapping the shaft alignment device, 6, directly onto the club shaft, 4, at the point where the bottom of the club handle, 7, meets the club shaft, 4. The user has the same options for removing the shaft alignment device, 6.

An enlarged version of the shaft alignment device, 8, shows its principal features, including the mounting clip, 9, spring arms, 10, level-indicating device, 11, bubble, 12, and alignment marks, 13. To minimize its size, weight, and cost, the mounting clip, 9, is an injection molded plastic such as ABS that possesses natural elasticity. The spring arms, 10, are dimensioned such that they can spring open and securely latch onto the club shaft, 4, without permanently deforming. The level-indicating device, 11, may be a bubble tube of the type commonly found in carpenter level tools, but may be any fluid-filled device containing a bubble that moves to the highest position inside the fluid chamber in response to different angles that the golf club shaft makes with the horizontal. The level-indicating device, 11, is oriented on the mounting clip, 9, such that the bubble, 12, is perfectly centered between the two alignment marks, 13, when the club shaft, 4, makes the ideal angle with the ground, 3.

FIG. 2 illustrates the preferred embodiment of the shaft alignment device, 8. This embodiment of the invention differs from the embodiment depicted in FIG. 1 in that the level-indicating device, 11, forms a downwardly curved arc of a circle. This downward curve allows the level-indicating device, 11, to measure the angle, 5, which the club shaft, 4, makes with the ground, 3. The bubble, 12, always comes to rest at the uppermost point of level-indicating device, 11, thereby allowing the level-indicating device, 11, to measure the angle, 5. This angle measurement capability allows the shaft alignment device, 8, to be used with multiple clubs carried by the golfer by scoring the level-indicating device, 11, with a plurality of alignment marks, 13, corresponding to the ideal alignment angle for each golf club.

Numerous modifications to and alternative embodiments of the present invention will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the best modes of carrying out the invention. Details of the system may be varied substantially without departing from the spirit of the invention and the exclusive use of all modifications which come within the scope of the appended claims is reserved. 

1-8. (canceled)
 9. A method for consistently achieving a specifically desired angle between the golf club shaft and the horizontal prior to initiating the golf swing, the method comprising: affixing to the side of the golf club shaft a circular spirit level device; orienting said circular spirit level device on the golf club shaft such that the arc of the circular spirit level device lies in a vertical plan that is parallel to the shaft; marking the curved surface of said circular spirit level device with a plurality of indicator lines that correspond to different golf club shaft angles.
 10. Apparatus that helps a golfer consistently achieve a specifically desired angle between the golf club shaft and the horizontal, comprising: a circular spirit level device that fits on the side of the golf club with the arc of the circular spirit level device laying in a vertical plane that is parallel to the golf club shaft; indicator lines, marked on the curved surface of said circular spirit level device, that correspond to different golf club shaft angles; an attachment device for anchoring said circular spirit level device to the golf club shaft, or grip, that is permanently affixed to said circular spirit level device so that said attachment device and said circular spirit level device form a single unit.
 11. Apparatus according to claim 10 in which said attachment device for anchoring said circular spirit level device to the golf club comprises: elastic members that sandwich the club and flex open to and accommodate golf club shafts and grips of different diameters; elastic members arranged so that they provide at least two separate gripping points with the golf club, along the axis of the golf club, to assure that the axis of said attachment device is aligned with the axis of the golf club to enable accurate and consistent readings of said circular spirit level device. 